Not sure I'm understanding exactly what you're try...

# tornadofx

[Shan]

Not sure I'm understanding exactly what you're trying to achieve, but the issue with the spacing is because the original theme doesn't have a borderColor set I believe. If you set a borderColor on the original theme, the squishing doesn't occur

[bjonnh]

I have a dark theme and the lines in the rows do not look good at all (too dark), so I wanted to make them lighter.